An Iron Age ‘defended enclosure’ – or hillfort – occupying a rocky crag towering above the Cist Cerrig chamber and Porthmadog.....
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According to Coflein it is:
‘A complex stone-walled enclosure, set on a broken, craggy summit. On the SW is an oval enclosure, c.26m E-W by 16m, having a rather larger, less well defined annex on the E. This is set on the perimeter of a larger, irregular enclosure, c.164m E-W by 94m, having a narrow annex projecting c.38m further E.‘